CN113382881A

CN113382881A - Ink jet printer with substrate height position control

Info

Publication number: CN113382881A
Application number: CN201980080041.7A
Authority: CN
Inventors: 迪格佰·潘; 苏-康·高亚历山大; C·多诺万大卫
Original assignee: Codiva
Current assignee: Codiva
Priority date: 2018-12-05
Filing date: 2019-12-05
Publication date: 2021-09-10
Anticipated expiration: 2039-12-05
Also published as: CN113382881B; WO2020118025A1; US20200180329A1; TW202021818A; US20210339543A1; US20230331008A1; KR20220122793A; KR102437326B1; KR20210098502A; TW202323068A; US11718111B2; CN116587749A; TWI797364B; US11097560B2

Abstract

An inkjet printer is described. The inkjet printer has a substrate holder assembly including a base member having a major axis in a first direction and a minor axis in a second direction perpendicular to the first direction; a contact member coupled to the base member, the contact member having a major axis in a first direction and a minor axis in a second direction; a holder bracket coupled to the base member; a linear extender coupled between the base member and the contact member and extending from the base member to the contact member in a third direction intersecting the first direction and the second direction; and a flexible member coupled to the base member, extending in a second direction between the linear extender and the contact member, and having a direction of deflection in a direction perpendicular to the first direction and the second direction.

Description

Ink jet printer with substrate height position control

Cross Reference to Related Applications

This application claims priority from U.S. provisional patent application serial No. 62/775,487 filed on 5.12.2018 and U.S. non-provisional patent application serial No. 16/702,380 filed on 3.12.2019, both of which are incorporated herein by reference.

Technical Field

Embodiments of the present invention generally relate to inkjet printers. In particular, methods and apparatus for monitoring and controlling the position and orientation of a substrate are described.

Background

Inkjet printing is common, whether in office and home printers, or in industrial-scale printers for manufacturing displays, printing large-scale writing materials, adding materials to articles such as PCBs, and building biological articles such as tissues. Most commercial and industrial ink jet printers, as well as some consumer printers, use dispensers to apply printing material to a substrate. The dispenser ejects a controlled amount of printing material toward the substrate at a controlled time and rate so that the printing material reaches a target location on the substrate and produces a mark having a desired size and shape.

In some cases, the precision with which the marking material is positioned on the substrate is very high. Minor deviations in the timing, quantity or speed of the ejection of the printing material can lead to printing failures. Similarly, inaccuracies in positioning the substrate to receive the printed material can result in off-target printed material reaching the substrate. For example, if the substrate is off target from the print jet, the printing material may travel an unintended distance and thus reach the substrate sooner or later. Substrate height control is required in high precision inkjet printing applications.

Summary of The Invention

Embodiments described herein provide a substrate holder assembly comprising: a base member having a major axis in a first direction and a minor axis in a second direction perpendicular to the first direction; a contact member coupled to the base member, the contact member having a major axis in the first direction and a minor axis in the second direction; a holder bracket coupled to the base member; a linear extender coupled between the base member and the contact member and extending from the base member to the contact member in a third direction intersecting the first direction and the second direction; and a flexible member coupled to the base member, extending in a second direction between the linear extender and the contact member, and having a direction of deflection in a direction perpendicular to the first direction and the second direction.

Other embodiments described herein provide an ink jet printer comprising a substrate support; a dispensing assembly attached to the substrate support; and a holder assembly attached to the substrate support, the holder assembly comprising a holder bracket operably coupled to a slide attached to the substrate support; a base member coupled to the holder bracket and having a long axis in a first direction along one side of a substrate support; a contact member coupled to the base member and having a long axis in the first direction, the contact member having a manipulator at an edge adjacent to a substrate support; a first linear extender coupled to the base member and extending from the base member toward the contact member at a location adjacent to an edge of the contact member having the manipulator; a first flexible assembly coupled to the base member and extending toward the manipulator; a second linear extender coupled to the base member and extending from the base member toward the contact member at a position adjacent to an edge of the contact member having the manipulator; and a second flexible assembly coupled to the base member and extending toward the manipulator.

Other embodiments described herein provide a substrate holder assembly comprising a holder carriage; a base member coupled to the holder bracket and having a long axis in a first direction; a contact member coupled to the base member such that the base member is between the holder bracket and the contact member, the contact member having a long axis in the first direction, the contact member having a manipulator extending along a long side of the contact member; a first linear extender coupled to the base member and extending through the base member to the contact member at a location adjacent to an edge of the contact member having a manipulator; a first flexible assembly coupled to the base member and extending toward the manipulator; a second linear extender coupled to the base member and extending through the base member to the contact member at a location adjacent to an edge of the contact member having a manipulator; and a second flexible assembly coupled to the base member and extending toward the manipulator.

Brief description of the drawings

So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

FIG. 1 is a top view of an inkjet printer according to one embodiment.

FIG. 2 is a plan view of a substrate support according to one embodiment.

FIG. 3 is a side view of a printing assembly according to one embodiment.

FIG. 4 is a top perspective view of a holder assembly for the inkjet printer of FIG. 1, according to one embodiment.

Fig. 5 is a cross-sectional view of a portion of the retainer assembly of fig. 4.

Fig. 6 is a detail view of a portion of the retainer assembly of fig. 4.

Fig. 7A is a plan view of the retainer assembly of fig. 4.

Fig. 7B is a cross-sectional view of a portion of the retainer assembly of fig. 4.

FIG. 8A is an activity diagram illustrating substrate edge positioning according to one embodiment.

FIG. 8B is an activity diagram illustrating substrate edge positioning according to another embodiment.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures, and it is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

Detailed Description

An ink jet printer is described herein that has a high degree of control to ensure accurate placement of the printed material on the substrate. FIG. 1 is a top view of an inkjet printer 100 according to one embodiment. The inkjet printer has a substrate support 102, a printing assembly 104, and a holder assembly 106 for manipulating the substrate for printing. Printer 100 is built on a base 108, which base 108 is typically a large object to minimize the transmission of vibrations to the operating components of printer 100. In one example, the base 108 is a granite block. The substrate support 102 is positioned on a base 108 and includes a support surface 110 and means for rendering the support surface 110 substantially frictionless. Here, the support surface 110 is an air table that provides an air cushion on which the substrate is floated. The support surface 110 has a plurality of holes 112 that allow the gas jets to exit, thus providing an upward force to maintain the substrate at a desired height above the support surface 110. Some of the holes may also allow for controlled withdrawal of gas from a gas cushion that floats the substrate support to provide precise local control of the substrate height.

The printing assembly 104 includes a dispenser assembly 114, the dispenser assembly 114 being disposed on a print support 116. The print support 116 is positioned relative to the substrate support 102 to provide a channel for the dispenser assembly 114 to be structurally positioned relative to the substrate on the substrate support 102 so that the printing material can be accurately applied to the substrate. Here, the print support 116 includes a rail or cross-beam 117 that traverses the substrate support 102, allowing the dispenser assembly 114 to traverse the substrate support 102 and deposit printing material anywhere on the substrate from one side of the print support 116 to the opposite side thereof. In this embodiment, a print support 116 is attached to the base 108 and extends from the base 108 to provide stable support for the dispenser assembly 114. Two stages 120 extend from the base 108 on opposite sides of the substrate support 102 to rails 117 that extend across the substrate support 102. Both the stage 120 and the rail 117 may be made of the same material as the base 108. In this case, the stage 120, the guide rail 117, and the base 108 are integrally formed of a piece of granite.

The dispenser assembly 114 generally includes one or more dispensers 119 and a print assembly controller 118, the print assembly controller 118 including electronics and sensors for controlling functional parameters of the dispenser 119 such as the position, timing, duration, type of printing material, and dispensing profile of the dispenser 119 along the print support 116. The dispenser 119 typically runs along the print support 116 by operation of a print carriage 122 coupled to the print support 116 to translate the dispenser 119 along the rail 117 from one end of the rail to the opposite end. The power and signal conduits are not shown to simplify the drawing.

The substrate is positioned below the printing assembly 104 by a holder assembly 106. The holder assembly 106 achieves secure contact with the substrate after substrate loading and moves the substrate along the substrate support 102 to position the substrate relative to the printing assembly 104 to dispense printing material onto the substrate in a precise manner. In this case, the holder assembly 106 is located on one side of the substrate support 102 and generally extends in a first direction along the substrate support 102 during printing to translate the substrate in the first direction. The first direction is represented in fig. 1 by arrow 124. The dispenser 119 is typically moved in a second direction substantially perpendicular to the first direction, as determined by a guide 117 extending substantially in the second direction, indicated in fig. 1 by arrow 126. The second direction 126 is sometimes referred to as the "x-direction" and the rail 117 is referred to as the "x-beam".

The holder assembly 106 is generally disposed on a holder assembly support 128, in this example, the holder assembly support 128 is a track that extends substantially the entire length of the substrate support 102 in the first direction along an edge 130 of the substrate support 102. In this embodiment, the holder assembly support 128 is attached to the base 108 to provide stable support for the holder assembly 106. The holder assembly support 128 may be made of the same material as the base 108. In this case, the holder assembly support 128, the base 108 and the print support 116 are integrally formed from a piece of granite. Sometimes, the holder assembly support 128 is referred to as a "y-beam".

The holder assembly 106 includes a holder carriage 132 that travels along the holder assembly support 128. Base member 134 is coupled to holder bracket 132, and contact member 136 is coupled to base member 134, with base member 134 interposed between holder bracket 132 and contact member 136. The contact member 136 includes a manipulator 138 positioned at an edge 140 of the contact member 136, the edge 140 being closest to the edge 130 of the substrate support 102. Here, a vacuum source (not shown) is coupled to the holder assembly 106 to provide a vacuum at the contact surface 142 of the manipulator 138 to securely hold the substrate on the substrate support 102 for processing. The holder assembly 106 moves along the holder assembly support 128 during operation to position the securely held substrate anywhere on the substrate support 102 so that, for example, through operation of the print assembly controller 118, the print assembly 104 can position the dispenser 119 to provide access to a precise location on the substrate to dispense the printed material.

The system controller 129 receives signals from various sensors that may be deployed throughout the printer 100 and sends signals to the system of the printer 100 to control printing. Here, the system controller 129 is shown operably coupled to the print assembly controller 118 and the holder assembly controller 131, the holder assembly controller 131 controlling the operation of the holder assembly 106. Each of the substrate support 102, printing assembly 104, holder assembly 106, and possibly other auxiliary systems, such as environmental control and material management systems, may have sensors operably coupled to the system controller 129 to send signals to the system controller 129 related to the status of the various components during printing operations. The system controller 129 includes data and instructions to determine the control signals sent to the various controlled components of the printer 100.

When printing on a substrate, it is often necessary to place tiny droplets of printing material (e.g., droplets of printing material 5-10 μm in diameter) in an area of the substrate that is 10-15 μm in size. In this operation, the printing material is typically dispensed as the substrate moves to minimize the printing time. The extreme accuracy to be achieved is complicated by minor imperfections in the dimensions of the various parts of the printing system, variations in these dimensions with temperature, inaccuracies in the translation speed of the substrate, dispenser assembly and holder assembly 106, and inaccuracies in the distance of the substrate from the dispenser 19. If the distance of the dispenser 119 to the substrate is not accurately known or controlled, the printing material drop velocity from the dispenser 119 cannot be programmed to cause the printing material drop to reach the target position when the substrate is in place. The drop arrives too early or too late and misses the target.

Described herein are apparatus and methods for controlling the distance (sometimes referred to as the "fly height") of a substrate from a dispenser 119 while the substrate is floating on a gas cushion. One or more sensors are included in the substrate support 102 or the printing assembly 104 to sense one or more distances of the substrate from, for example, certain portions of the substrate support 102 or the printing assembly 104. FIG. 2 is a plan view of a substrate support 200 according to one embodiment. The substrate support 200 may be used as the substrate support 102 in the printer 100 of fig. 1. The substrate support 200 comprises a first plurality of holes 202 formed in the support surface 201 of the substrate support 200 for providing a gas between the support surface 201 and a substrate disposed thereon to establish a gas cushion that supports the substrate at a target height above the support surface 201. The substrate support 200 also includes a second plurality of apertures 204 formed in the support surface 201 for providing suction between the support surface 201 and a substrate disposed thereon. A gas source (not shown) comprising an inert gas is fluidly coupled to the first plurality of apertures 202, and a vacuum source (not shown) is fluidly coupled to the second plurality of apertures 204. The gas source and the vacuum source are operated to provide a gas cushion having a target thickness and/or pressure between the substrate and the support surface 201. Here, the first plurality of holes 202 are substantially evenly distributed over the entire support surface 201 from one end to the other end of the support surface 201, and completely across the support surface 201. The second plurality of apertures 204 are interspersed with the first plurality of apertures 202 in a central region 205 of the support surface 201. In the central region 205, the vacuum provided through the second plurality of apertures 204 works in conjunction with the gas cushion provided through the first plurality of apertures 202 to provide control of the height of the substrate above the support surface 201 in the central region 205, where deposition of the printing material on the substrate occurs in the central region 205.

A plurality of distance sensors 206 are disposed in the support surface 201 to sense the distance between the substrate and the support surface 201. Because the substrate may be large, multiple sensors 206 may be used to sense distances at multiple portions of the substrate. In other cases, a single sensor 206 may be used. Here, the sensors 206 are shown regularly spaced in the support surface 201. The sensor 206 may be capacitive, inductive, optical or acoustic, or a mixture thereof. In one embodiment, only capacitive sensors are used. In another embodiment, a capacitive sensor and an optical sensor are used. The optical sensors may be interferometric, diffractive, spectral and/or triangulation based. The distance sensor 206 is operatively coupled to the system controller 129 (fig. 1), and sends a signal representative of the sensed distance to the system controller 129. Each sensor 206 transmits a signal related to the distance of the substrate from the sensor 206, along with an identification code. The system controller 129 receives the signal and the identification code and stores them. The system controller 129 also converts the signal to a distance and may convert the identity code to a position of the support surface 201 based on a predetermined mapping of the sensors 206.

The type and density of the sensors 206 may vary across the support surface 201. For example, if no distance to the support surface 201 is sensed in certain areas of the support surface 201, that area may not have a sensor 206. If the low granularity of the distance measurements is sufficient in certain areas, the area may have a low density of sensors 206. If high granularity measurements are required in other areas, the area may have a high density of sensors 206. In this case, the support surface 201 has a high granularity of the sensor 206 in the region close to the print assembly 104 for dispensing the printing material, so that the distance between the substrate and the dispenser 119 (fig. 1) can be more precisely controlled.

In another embodiment, one or more sensors may be attached to the printing assembly. FIG. 3 is a side view of a printing assembly 300 according to one embodiment. Printing assembly 300 may be used as printing assembly 104 in printer 100 of fig. 1. Printing assembly 300 includes similar elements as printing assembly 104 of fig. 1, which will be labeled with the same reference numerals. The printing assembly includes one or more sensors 302 for sensing the distance of the substrate. Here, one sensor 302 is shown mounted on the print support 116. Another sensor 302 is shown mounted on the print carriage 122. Additionally, another sensor 302 is shown mounted on one of the dispensers 119. Any or all of these sensors 302 may be used to sense the relative distance of the substrate. If multiple sensors 302 are possible to use with the sensor 206 in the support surface 201 of the substrate support 200, the system controller 129 may compare multiple distance readings and may obtain a distance estimate with improved accuracy. The sensor 302 may be optical or acoustic. Any of the optical sensors described above may be used for the sensor 302. The sensor 302 is shown here operably coupled to the print assembly controller 118 to send a signal representative of the distance reading to the print assembly controller 118. It should be noted that the sensors 302 and other operable elements of the printing assembly 104 may be directly operably coupled to the system controller 129 without the use of a printing assembly controller.

The substrate height can be controlled by adjusting the gas cushion supporting the substrate. If the substrate height is adjusted up or down, a slight curvature may occur near the edge of the substrate that contacts the holder assembly without adjusting the holder assembly. Fig. 4 is a perspective view of a retainer assembly 400 according to one embodiment. The holder assembly 400 has the ability to adjust the edge of the substrate in a direction perpendicular to the support surface 201 of the substrate support 200 (or 102). The holder assembly 400 may be used as the holder assembly 106 described above.

The holder assembly 400 has a bracket member 402, a base member 404 coupled to the bracket member 402, and a contact member 406 coupled to the base member 404 such that the base member 404 is interposed between the contact member 406 and the bracket member 402. The contact member 406 contacts the substrate along the edge using a vacuum to form a stable firm contact with the substrate. A vacuum source (not shown) is fluidly coupled to holder assembly 400 to provide a vacuum force. The bracket member 402 supports substantially frictionless movement of the holder assembly 400 along the holder assembly support 128.

The base member 404 has a major axis 405 extending along the first direction 124 that is substantially the same size as the support surface 201 (fig. 2) of the substrate support 102 in the first direction 124. The base member 404 has a minor axis 407 in the second direction 126. The base member 404 may be plate-shaped and may have various openings for fasteners, sensors, actuators, and the like. The base member 404 is secured to the bracket member 402 to provide stable support for the contact member 406 as the bracket member 402 translates along the holder assembly support 128. In this embodiment, the base member 404 extends beyond the ends of the bracket member 402 in the first direction 124, and the bracket member 402 is centered with respect to the base member 404. Here, the outline of the base member 404 is rectangular.

The contact member 406 is adjustably coupled to the base member 404. The contact member 406 includes a fulcrum 408, a manipulator stage 410, a manipulator 412 coupled to the manipulator stage, and a plurality of landing members (discussed further below) for mounting sensors and/or positioners as described below. The contact member 406 has a major axis 409 in the first direction 124 and a minor axis 411 in the second direction 126 and is substantially similar in length to the base member 404. Like the base member, the contact member 406 also has a rectangular profile because the fulcrum 408, manipulator stand 410, and manipulator 412 all extend substantially the length of the base member 404. The manipulator stage 412 is located adjacent to a support edge 416 of the contact member 406 of the substrate support 102 and adjacent to an access edge 418 of the base member 404. Fulcrum 408 is located at an adjustment edge 420 of contact member 406 opposite support edge 416, and adjacent to a corresponding opposite edge 422 of base member 404.

Fig. 5 is a cross-sectional view of the retainer assembly 400 of fig. 4. The linear extender 502 is coupled to the base member 404 and extends from the base member 404 toward the contact member 406. The linear extender 502 is located at the support edge 416 of the contact member 406 and extends in a third direction 504 perpendicular to the first and second directions toward the contact member 406. The linear stretcher 502 may also extend slightly in either or both of the first direction 124 and the second direction 126. The linear stretcher 502 may be any precision positioner, such as a piezoelectric positioner, capable of positioning an object with an accuracy of less than 10 μm. In a piezoelectric embodiment, when a voltage is applied, a sample of piezoelectric material is oriented to change length in a third direction, and the degree of length change is directly and precisely related to the applied voltage.

The bearing member 506 is disposed between the linear extender 502 and the contact member 406. The bearing member 506 is disposed adjacent the base member 404 at the support edge 416 of the contact member 406. The linear extender 502 applies the positioning force to the bearing member 506, which bearing member 506 in turn transmits the positioning force to the contact member 406. The bearing member 506 extends in the first direction 124 and has a length substantially the same as the length of the contact member 406 in the first direction 124. Thus, the bearing member 506 extends along substantially the entire length of the contact member 406 in the first direction 124. Here, the bearing member 506 is hollow to reduce weight, and the bearing member 506 has a dimension in the second direction 126 that is greater than a dimension of the manipulator stage 410 of the contact member 406 in the second direction 126.

A landing member 508 is disposed between the bearing component 506 and the manipulator gantry 410. The landing member 508 adjusts the positioning force exerted by the linear extender 502 on the contact member 406. The landing member 508 may be made of a strong resilient material to absorb any impulse or shock that may be transmitted between the contact member 406 and the bearing member 506. In other cases, the landing member 508 may be an air bearing. A plurality of landing members 508 are distributed along the length of the bearing member 506 and the manipulator gantry 410 to provide stable and consistent positioning support along the length of the manipulator gantry 410.

The linear extender 502 changes length in a third direction 504 when actuated. As the linear extender 502 is extended, the bearing member 506 is urged toward the contact member 406 in the third direction 504 to move the position of the support edge 416 of the contact member 406 in the third direction 504. When the substrate is positioned on the manipulator 412, the substrate contacts the manipulator 412 at the contact surface 510. Vacuum is applied to contact surface 510 through vacuum manifold 512, which is a conduit that passes through manipulator 412 along the length of manipulator 412 in first direction 124. The pressure differential created by the vacuum forces the substrate against the contact surface 510 such that the substrate moves with the manipulator 412, the manipulator stage 410, and the contact member 406. At the support edge 416, the manipulator 412 is moved in a third direction 504 by operating the linear extender 502 such that the height of the substrate above the substrate support 102 proximate the holder assembly 400 is modified.

Referring again to fig. 4, the contact member 406 includes a plurality of brackets 424 that couple the manipulator carriage 410 to the fulcrum 408. Here, there are four brackets 424, two at opposite ends of fulcrum 408 and two near the center of the sides of contact member 406. In this case, the dimension of the fulcrum 408 in the first direction 124 is smaller than the dimension of the manipulator stage 410 in the first direction 124. Bracket 424 serves to securely couple fulcrum 408 to manipulator carriage 410 so that the two move as a unit, and contact member 406 has structural integrity. The bracket 424 is here oriented along the second direction 126 and is a rod-like member that extends from the fulcrum 408 to the manipulator stand 410. Each bracket 424 is disposed between the fulcrum 408 and the base member 404 and between the manipulator carriage 410 and the bearing member 506, and each bracket 424 is in direct contact with both the fulcrum 408 and the manipulator carriage 410. Each bracket 424 also forms a right angle with the fulcrum 408 and the manipulator carriage 410.

One bracket 424 is visible in fig. 5. A second grounding member 508 is disposed between base member 404 and fulcrum 408, shown here behind bracket 424. The secondary landing member 508 supports the fulcrum 408 at the adjustment edge 420 of the contact member 406. As the linear extender 502 is extended, moving the bearing member 506, the landing member 508, the manipulator carriage 410, and the manipulator 412 in the third direction 504, the bracket 424 couples the movement of the aforementioned members at the support edge 416 to the fulcrum 408 at the adjustment edge 420. Because the positioning force of linear extender 502 is not directed through the centroidal axis of contact member 406, contact member 406 rotates such that fulcrum 408 does not move in third direction 504. The contact member 406 thus forms an angle θ with respect to the base member 404. The angle θ typically ranges up to a few micro radians, for example from zero to 100 micro radians. The secondary landing member 408 may also be an air bearing.

The base member 404 includes a support block 428, the support block 428 supporting a first flexible member 430 and a second flexible member 432 that form a pair of flexible members. The support block 428 has a first side 434 that contacts the base member 404. Here, the second landing member 508 contacts the base member 404 on a first side 514, and the support block 428 contacts the base member 404 on a second side 516 opposite the first side 514. The base member 404 is thus disposed between the second landing member 408 and the support block 428. The first side 514 of the base member 404 has a shelf 518 located between the second landing member 508 and the access edge 418 of the base member 408. At the shelf 518, the thickness of the base member 404 changes from a first thickness between the support block 428 and the second landing member 508 to a second thickness that is less than the first thickness. Thus, the thickness of the base member 404 decreases at the shelf 518 as the base member 404 extends from a position adjacent the fulcrum 408 to a position toward the manipulator stand 410.

A first flexible member 430 is attached to a first side 514 of the base member 404 between the fulcrum 408 and the base member, the first side 514 being opposite where the support block 428 is attached to a second side 516 of the base member 404. The first flexible member 430 extends in the second direction 126 toward the manipulator stand 410 beyond the shelf 518 and the access edge 418 of the base member. At the shelf 518, a gap 520 is formed between the first flexible member 430 and the base member 404, the gap 520 allowing the first flexible member 430 to freely flex in the third direction 504. Thus, the first flexible member 430 has a direction of deflection in the third direction 504. The first flexible member 430 extends to a position between the bearing member 506 and the manipulator carriage 410. The first flexible member 430 is secured to the base member 404 by a first capture plate 522, the first flexible member being disposed between the base member 404 and the first capture plate 522 and secured by a convenient fastener (e.g., a bolt). First flexible member 430 is secured to bearing member 506 at a first side 528 of bearing member 506 by second capture plate 524, with first flexible member 430 disposed between second capture plate 524 and bearing member 506. In this manner, when the bearing member 506 is moved in the third direction 504 by the linear extender 502, the first flexible member 430 bends in the third direction 504 to provide a restoring force opposing the positioning force of the linear extender 502. As can be seen in fig. 5, the landing member 508 is in supporting relation with the first side 528 of the bearing member 506 and with the manipulator stand 410.

A second flexible member 432 extends from a second side 526 of the support block 428 opposite the first side 434 and is secured to the second side 526 of the support block 428 by a third capture plate 530, the third capture plate 530 being secured to the support block 428 by a convenient fastener such as a bolt. Here, the first member 430 and the second member 432 have the same length. The second flexible member 432 extends in the second direction 126 toward the bearing member 506. Here, the bearing member 506 is a hollow tube having a square profile. The second flexible member 432 is attached to a second side 532 of the bearing member 506 opposite the first side 528. Second flexible member 432 is secured to second side 532 of bearing member 506 by a fourth capture plate 534, and second flexible member 432 is disposed between fourth capture plate 534 and second side 532 of bearing member 506. The fourth capture plate 534 is secured to the second side 532 of the bearing member 506 by a convenient fastener, such as a bolt.

Linear extender 502 is disposed here through second side 532 of bearing member 506 to contact first side 528 of bearing member 506 at inner surface 536 of first side 528. A pressure member 538 at the force-bearing end 540 of the linear extender 502 contacts the inner surface 536 of the first side 528. The pressure member 538 applies a positioning force to the inner surface 536 of the first side 528 of the bearing member 506. The bearing member 506 contacts the first flexible member 432 at an outer surface 542 of the first side 528, thereby transmitting the positioning force to the manipulator table 410 of the contact member 406, and thus to the manipulator 412, via the first flexible member 432. The manipulator 412 moves to a precise position determined by actuation control (e.g., voltage in the case of a piezoelectric element) applied to the linear extender 502 in response to a positioning force applied by the linear extender 502. The linear stretcher 502 enables precise positioning of the edge of the substrate in the third direction 504 when in contact with the substrate disposed on the substrate support 102. Thus, the linear stretcher 502 accurately affects the height of the edge region of the substrate above the substrate support 102, thereby preventing contact between the edge region and the substrate support surface 201 in the event of a change in substrate height in other regions. In this case, the linear stretcher 502 has a range of motion of about 100 μm, which may be selected based on the particular architecture and scale of the system. The first and second

flexible members

430 and 432 and under the directional gravity provide a restoring force on the bearing member 506 that opposes the positioning force of the linear extender 502 such that when actuation of the linear extender 502 is interrupted or reduced, the restoring force of the

flexible members

430 and 432 moves the bearing member 506 in a direction opposite to the direction of the positioning force, thereby reducing the height of the substrate at the edge of the substrate support 102.

The linear extender 502 is supported by an extension 546 of the base member 404 that extends from the second side 516 of the base member 404 in the second direction 126 toward the bearing member 506. The stirrup 544 extends from the extension 546 in alignment with the linear extender 502 positioned in the stirrup 544. Here, the linear extender 502 is a cylinder, the axis of which extends in the third direction 504, and may also extend slightly in the first direction 124 and the second direction 126. The linear extender 502 is seated in the stirrup 544 with a support end 548 opposite the force bearing end 540. The linear extender 502 extends through the fourth capture plate 534, the second flexible member 432, and the second side 532 of the bearing member 506 to the interior of the bearing member 506, ultimately to the force bearing end 540 and the pressure member 538 against the inner surface 536 of the first side 528 of the bearing member 506. When actuated, the linear extender 502 thus creates a separation force between the stirrup 544 and the bearing member 506 to move the bearing member 506 in the third direction 504 relative to the stirrup 544 and the base member 404 to which the stirrup 544 is attached. As described above, when actuation of linear extender 502 ceases or subsides,

flexible members

430 and 432 reverse the movement in third direction 504.

Referring again to fig. 4, the retainer assembly 400 has two linear extenders (not visible in fig. 4) positioned to provide a steady positioning force to the contact members 406, one on each side of the centerline of the contact members 406. The position of the linear extenders can be seen with reference to the two support blocks 428, the first flexible member 430 and the

capture plates

522, 524 and 530. The bearing member 506 is also visible. If desired, the two linear extenders allow the two ends or sides of the contact member 406 to be actuated differently in the third direction 504 to provide the ability to rotatably position the substrate about the axis of the second direction 126, sometimes referred to as theta-x positioning capability. Each linear extender has a pair of flexible members, as shown in fig. 5, with reference to a first flexible member 430 and a second flexible member 432. Each pair of flexible members and each linear extender are coupled to the apparatus as shown in fig. 5.

The linear extender 502 described above cooperates with the

flexible members

430 and 432 to position the manipulator 412 in the third direction 504, and thus the linear extender 502 is sometimes referred to as a z-positioner. The holder assembly 402 also has a linear positioner 436. In the version of fig. 4, near opposite ends of the holder assembly 402, there are two linear locators 436, a first linear locator 436 and a second linear locator 436. Each linear positioner 436 is disposed alongside a respective encoder 438 and positions the contact member 406 in the second direction 126 by applying a positioning force to the contact member 406 in the second direction 126. Each linear positioner 436 includes an extension member 442 disposed in a receptacle 444 and abutting a wall 446. One of the linear positioners 436 and the encoder 438 can be seen in FIG. 5. The extension member 442 has a first end abutting the wall 446 and a second end disposed in the receptacle 444. The encoder 438 includes a pair of posts 552 on which the scale 550 is supported. The struts 552 are attached to the legs 424 of the contact member 406. The side walls 556 of the receptacles 444 are visible between the struts 552 and pass through the gap between the bracket 424 and the first flexible member 430. The receptacle 444 is attached to the base member 404. Wall 446 is attached to fulcrum 408 of contact member 406. The readhead 554 is attached to the receptacle 444 and projects into alignment with the scale 550.

Fig. 6 is a detailed view of one of the linear positioner 436 and the encoder 438 of the holder assembly 400 of fig. 4. This view is looking from the position of fulcrum 408 toward manipulator stand 410. The extension member 442 is visibly disposed within the receptacle 444 and extends out of the plane of the figure. The read head 554 includes a support 602 attached to the receptacle 444 and a reader 604 attached to the support 602. The reader 604 is aligned with a metrology member 608 located above a scale 550 of the encoder 438. The support 552 supports the scale 550 from one side such that the scale 550 extends from the support 552 toward the receiving portion 444. Thus, the reader 604 may be positioned between the scale 550 and the support 424 in alignment with the metrology member 608. The metrology member 608 is disposed at an outer surface 610 of the scale 550 facing the reader 604.

The encoder 438 generates a signal indicative of the position of the reader 604 relative to the metrology member 608. The metrology member 608 is attached to the contact member 406 by manipulating posts 552 attached to the supports 424. The reader 604 is attached to the base member 404 by operation of the support 602 and the receptacle 444. If the contact member 406 is moved in the third direction 126 relative to the base member 404, the reader 602 records the positional offset of the metrology member 608. To compensate for this displacement, the extension member 442 can be energized to apply a positioning force in the second direction 126 to the wall 446 (fig. 5), and thus to the fulcrum 408 of the contact member 406. The extension member 442 is a bi-directional positioner, meaning that energy may be applied to extend or retract the extension member 442. The extension member 442 may be a pneumatic, electromagnetic, electromechanical, or any bi-directionally actuatable extension member.

Referring again to fig. 5, as the linear extender 502 (one of the two in the embodiment of fig. 4) extends in the third direction 504, rotation of the contact member 406 changes the angle θ of the contact member 406 relative to the base member 404. In addition to causing movement of the manipulator 412 in the third direction 504, this also causes movement of the manipulator 412 in the second direction 126. The encoder 438 records this movement in the second direction 126 and sends a signal to the holder assembly controller 131 (fig. 1) indicating the position of the contact member 406 relative to the base member 404 or to the system controller 129 in the absence of a separate holder assembly controller 131. In response, if the recorded motion is not within the tolerance range, the holder assembly controller 131 or the system controller 129 may send a signal to energize the linear positioner 438 to adjust the position of the contact member 406 in the second direction 126. As shown in fig. 4, there are two linear locators 438 in the holder assembly 400, as described above. The two linear positioners 438 may be energized together to adjust the position of the entire contact member 406 in the second direction 126 to compensate for any misalignment in the second direction 126 due to rotation of the contact member 406 or due to any other misalignment in the inkjet printer 100.

Referring again to fig. 4, the contact member 406 is coupled to the base member 404 by a pivot 443 located near the center of both the contact member 406 and the base member 404. The pivot 443 is coupled to the base member 404 and extends through the contact member 406 between the two supports 424 near the center of the contact member 406. The flexible plate 450 is disposed about the pivot 443 and extends to the support 424 on either side of the pivot. The flexible plates 450 are secured to the two supports 424 by respective capture plates 452, the capture plates 452 being secured to the supports 424 by convenient fasteners (e.g., bolts).

Fig. 7A is a top view of the contact member 406 of fig. 4. Substrate 702 is shown held on manipulator 412. For reference purposes, components around the two second linear locators 438 are shown. The pivot 443 includes a pivot post 704, the pivot post 704 extending through the contact member 406 near the center thereof. Pivot posts 704 extend through flexible plate 450. The flexible plate 450 allows the contact member 406 to move in the third direction 504 in accordance with the positioning force applied by the linear extender 502.

Fig. 7B is a cross-sectional view of a portion of the contact member 406 of fig. 4. Pivot post 704 has a first end 720 and a second end 722. The first end 720 extends through the flexible plate 450 and the second end 722 has a flange 724 coupled to a slide member 726.

The sliding member 726 has a first surface 728, a second surface 730, and an aperture 732 through the sliding member 726 from the first surface 728 to the second surface 730. Pivot post 704 extends through an aperture 732 in the slide member. The sliding member 726 has a third surface 734 that couples the first surface 728 with the second surface 730. Sliding member 726 also has a fourth surface 736 opposite third surface 734 and also coupling first surface 728 with second surface 730.

A first groove 738 is formed in the third surface 734. A second groove 740 is formed in the fourth surface 736. A first guide member 742 extends from the base member 404 and engages the first groove 738. A second guide member 744 extends from the base member 404 and engages the second recess 740. The slide member 726 slides along the

guide members

742 and 744 to allow the slide member 726 to move in the second direction 126 (fig. 7A).

In this case, the pivot post 704 is secured to the slide member 726 by a recess 746 formed in the second surface 730 of the slide member 726 around the hole 732. The flange 724 engages the recess 746 and is captured in the recess 746 between the slide member 726 and the base member 404. Pivot post 704 extends through flexible plate 450 and is attached to flexible plate 450 by a central capture plate 710. The center capture plate 710 and the flexible plate 450 each have an opening that allows rotational movement of the center capture plate 710 and the flexible plate 450 about the pivot post 704. In this manner, the contact member 406 may rotate about the pivot post 704. The movement of the sliding member 726 allows the contact member 406 to move in the second direction 126. In another embodiment, pivot post 704 may be attached to sliding member 726. In the embodiment shown in fig. 7B, the second end 730 of the pivot post 704 may rotate within the recess 746 relative to the base member 404 to obtain additional rotational freedom between the base member 404 and the contact member 406.

In this way, the linear extender 502 may be actuated in accordance with signals received from the system controller 129 or the holder assembly controller 131 to position the edge of the substrate 702 at a target height above the support surface 201 of the substrate support 200 or 102. The flexible plate 450 flexes with movement of the contact member 406 in the third direction 506, providing an additional restoring force against the action of the linear extender 502. The linear positioner 438 may be actuated in accordance with signals received from the system controller 129 or the holder assembly controller 131 to compensate for displacement in the second direction 126 caused by movement of the manipulator 412 in the third direction 504 and concomitant rotation of the contact member 406. The sliding member 726 allows the contact member 406 to move in the second direction 126 in response to the positioning of the linear positioner 438. Finally, the linear positioner 438 may be actuated differently to compensate for any misalignment of the substrate 702 or imperfections in the positioning of the

holder assembly

400 or 106 on the holder assembly support 128. Pivot post 704 allows contact member 406 to rotate about pivot post 704 according to the differential positioning applied by linear positioner 438. The system described herein enables precise positioning of the substrate 702 for printing operations.

As described above, the holder assembly described herein has the ability to adjust the position of the edge of the substrate in the third direction and thus the distance between the substrate and the substrate support at the edge region of the substrate. This function may be useful if the overall position of the substrate in the third direction changes. In this case, the position of the edge region of the substrate may be changed to be adapted. FIG. 8A is an activity diagram illustrating substrate edge positioning using embodiments described herein. Substrate 826 is positioned above substrate support 802 for processing. The printing material will be ejected from the dispenser 828 onto the substrate 802, which substrate 802 is supported above the substrate support 802 by a gas cushion. A holder assembly 822, which may be one of any of the holder assemblies described herein, is positioned adjacent to the substrate support 802. The retainer assembly has a contact surface 824, such as contact surface 510 of fig. 5. Substrate 826 is held against contact surface 824 by suction. The substrate support 802 forms a gas cushion that supports the substrate 826 between the dispenser 828 and the substrate support 802. The substrate support 802 has a flat top surface 832. Substrate 826 is also flat and has a uniform separation distance between dispenser 828 and the top surface of substrate 826 in first section 833. In the second region 831, the substrate 826 is deflected to enter the contact surface 824. Thus, the top surface of the substrate 826 has a non-uniform separation distance from the dispenser 828. The holder assemblies described herein have the ability to move in a third direction to correct for such uneven separation. Thus, if the separation distance of the substrate 826 from the dispenser 828 is not uniform due to deflection of the substrate toward the contact surface 824, the holder assembly 822 can be adjusted in a third direction to eliminate the deflection.

FIG. 8B is another activity diagram illustrating substrate edge positioning according to another embodiment. In this case, a substrate support 850 having a tapered edge 852 is used. The tapered edge 852 of the substrate support 850 is adjacent to the retainer assembly 822. The support surface 854 of the substrate support 850 recedes away from the substrate at the tapered edge 852 in a direction toward the holder assembly 822. In other words, the distance from the tapered edge 852 to the substrate 826 decreases with distance from the retainer assembly 822. The tapered edge 852 minimizes edge effects in the processing of the substrate, thereby facilitating adjustment of the edge region in a third direction to eliminate non-uniformity in the spacing between the substrate 826 and the dispenser 828 without risk of contact between the substrate 826 and the support surface 854.

The tapered edge 852 is generally linear. That is, the tapered edge 852 is a flat surface that forms an angle of between about 1 ° and about 20 °, such as about 5 °, with the support surface 854. The width 851 of the tapered edge 852 in a direction parallel to the support surface 854 is about 10mm to about 30mm, but may be greater than 30 mm. Here, the tapered edge 852 is shown forming a corner with the support surface 854. The corner may be sharp, as schematically depicted herein, or may be rounded or chamfered. For example, a slight chamfer having a radius of about 0.1mm may be applied to the junction between the tapered edge 852 and the support surface 854.

While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

1. A substrate holder assembly comprising:

a base member having a major axis in a first direction and a minor axis in a second direction perpendicular to the first direction;

a contact member coupled to the base member, the contact member having a major axis in a first direction and a minor axis in a second direction;

a holder bracket coupled to the base member;

a linear extender coupled between the base member and the contact member and extending from the base member toward the contact member in a third direction intersecting the first direction and the second direction; and

a flexible member coupled to the base member, extending in the second direction, disposed between the linear extender and the contact member, and having a direction of deflection in a direction perpendicular to the first direction and the second direction.

2. The substrate holder of claim 1, further comprising: a bearing member disposed between the linear extender and the flexible member and extending in the first direction.

3. The substrate holder of claim 2, wherein the bearing member is a hollow tube.

4. The substrate holder of claim 3, wherein the hollow tube has a square profile.

5. The substrate holder of claim 4, wherein the flexible member is a first flexible member, and further comprising a second flexible member, wherein the first flexible member and the second flexible member define a flexible member pair.

6. The substrate holder of claim 5, wherein the first flexible member extends between the bearing member and the contact member on a first side of the bearing member and the second flexible member extends on a second side of the bearing member opposite the first side.

7. The substrate holder of claim 6, wherein the base member comprises a support block separating the first flexible member and the second flexible member.

8. The substrate holder of claim 1, wherein the base member is a base plate.

9. The substrate holder of claim 1, wherein the linear extender is a first linear extender, and further comprising a second linear extender coupled to the base member and extending from the base member in a third direction toward the contact member.

10. The substrate holder of claim 9, wherein the pair of flexible members is a first pair of flexible members and further comprising a second pair of flexible members coupled to the bearing member.

11. The substrate holder according to claim 10, wherein the flexible members of the second pair of flexible members extend to opposite sides of the bearing member.

12. The substrate holder of claim 11, wherein the substrate member comprises a first support block separating the flexible members of the first pair of flexible members and a second support block separating the flexible members of the second pair of flexible members.

13. An ink jet printer comprising:

a substrate support;

a dispensing assembly attached to the substrate support; and

a holder assembly attached to the substrate support, the holder assembly comprising:

a holder bracket operably coupled to a slide attached to the substrate support;

a base member coupled to the holder bracket and having a long axis in a first direction along one side of the substrate support;

a contact member coupled to the base member and having a long axis in a first direction, the contact member having a manipulator at an edge of the contact member adjacent to the substrate support;

a first linear extender coupled to the base member and extending from the base member toward the contact member at a position adjacent to an edge of the contact member having the manipulator;

a first flexible assembly coupled to the base member and extending toward the manipulator;

a second linear extender coupled to the base member and extending from the base member toward the contact member at a position adjacent to an edge of the contact member having the manipulator; and

a second flexible assembly coupled to the base member and extending toward the manipulator.

14. The inkjet printer of claim 13, wherein the holder assembly further comprises a bearing member between the base member and the contact member at an edge of the contact member having the manipulator.

15. The inkjet printer of claim 14, wherein each of the first and second flexible assemblies comprises: a first flexible member extending between the bearing member and the contact member on a first side of the bearing member; and a second flexible member extending to a second side of the bearing member opposite the first side of the bearing member.

16. The inkjet printer of claim 15, wherein each of the first and second flexible assemblies comprises a support block separating the first and second flexible members.

17. The inkjet printer of claim 16, wherein the holder assembly further comprises a first linear positioner and a second linear positioner, each of the linear positioners being coupled to the base member and extending to the contact member in a second direction perpendicular to the first direction.

18. The inkjet printer of claim 13, wherein the substrate support has a tapered edge adjacent the retainer assembly.

19. A substrate holder assembly comprising:

a holder bracket;

a base member coupled to the holder bracket and having a long axis in a first direction;

a contact member coupled to the base member such that the base member is between the holder bracket and the contact member, the contact member having a long axis in a first direction, the contact member having a manipulator extending along a long side of the contact member;

a first linear extender coupled to the base member and extending through the base member to the contact member at a location adjacent to an edge of the contact member having the manipulator:

a second linear extender coupled to the base member and extending through the base member to the contact member at a position adjacent to an edge of the contact member having the manipulator; and

20. A substrate holder assembly comprising:

a substrate contacting member comprising a manipulator having a vacuum surface;

a first actuator that moves the substrate contact member in a first direction;

a second actuator that moves the manipulator in a second direction perpendicular to the first direction; and

a third actuator that moves the manipulator in a third direction perpendicular to the first direction and the second direction.

21. The substrate holder assembly of claim 20, wherein the second and third actuators are members of the substrate contacting member.

22. The substrate holder assembly of claim 20, wherein the third actuator comprises two linear actuators operable to rotate the manipulator about an axis extending in the second direction.

23. The substrate holder assembly of claim 22, wherein the second actuator comprises two linear actuators operable to rotate the manipulator about an axis extending in the third direction.

24. The substrate holder assembly of claim 23, further comprising a pivot between the two linear actuators of the second actuator.

25. An ink jet printer comprising:

a substrate support;

a dispensing assembly attached to the substrate support; and

a substrate holder assembly attached to the substrate support, the substrate holder assembly comprising a manipulator movable in three perpendicular directions.

26. The inkjet printer of claim 25, wherein the substrate holder assembly includes a holder carriage having a linear actuator that can move the manipulator in a first direction, and a plurality of actuators that can move the manipulator in a second direction perpendicular to the first direction and a third direction perpendicular to the first and second directions.

27. The inkjet printer of claim 26, wherein the plurality of actuators includes a first pair of linear actuators capable of moving the manipulator in a second direction and a second pair of linear actuators capable of moving the manipulator in a third direction.

28. The inkjet printer of claim 27, wherein the first pair of linear actuators is operable to rotate the manipulator about an axis extending in the third direction.

29. The inkjet printer of claim 28, wherein the second pair of linear actuators is operable to rotate the manipulator about an axis extending in the second direction.

30. The inkjet printer of claim 29, wherein the substrate holder assembly further comprises a position compensator that operates the first pair of linear actuators to compensate for movement of the manipulator in the second direction due to movement of the manipulator in the third direction.

31. A substrate holder assembly comprising:

a holder bracket coupled to the base member;

a flexible member coupled to the base member and the contact member, extending in the second direction, and having a direction of deflection in a direction perpendicular to the first direction and the second direction.